A data center is a facility that houses servers, data storage devices, and/or other associated components such as backup power supplies, redundant data communications connections, environmental controls such as air conditioning and/or fire suppression, and/or various security systems. A data center may be maintained by an information technology (IT) service provider. An enterprise may purchase data storage and/or data processing services from the provider in order to run applications that handle the enterprises' core business and operational data. The applications may be proprietary and used exclusively by the enterprise or made available through a network for anyone to access and use.
Data centers may use large amounts of electrical power. For example, a rack of servers may use a few kilowatts of electrical power, while numerous racks of servers housed in a large data center may use on the order of hundreds of megawatts of power over the same time period. Additional devices and support resources in the data center may use additional power. A large data center may use more than 100 times the amount of power used by an office building. The amount of power used for computing in a data center may scale up with faster and/or bigger servers. Power costs for a data center may account for more than 10% of the total operating cost of the data center. More power demand may equate with more operational costs and more environmental stress.